EPA Proposes Updated Protection for Boston Coastal Waters in New Draft Permit for MWRA Deer Island Facility and 43 Contributing Communities | US EPA

Draft Permit includes provisions to address climate impacts and lingering combined sewer overflows

May 31, 2023

BOSTON – The U.S. Environmental Protect Agency (EPA) has issued an updated draft permit under the Clean Water Act for the Massachusetts Water Resources Authority (MWRA) Deer Island Treatment Plant and several effluent outfalls associated with the system.

The proposed permit would significantly update protections for Boston Harbor and Massachusetts Bay by bringing water quality protections in line with other more recent permits, including adding as co-permittees the 43 communities whose wastewater flows to the Deer Island facility for treatment before being discharged into Massachusetts Bay. EPA is accepting public comment on the Draft Permit until July 31, 2023. The Deer Island Treatment Plant provides secondary treatment to wastewater from 43 cities and towns in the Greater Boston area.

“This proposed clean water permit is an important milestone for updating protections for Boston Harbor and Massachusetts Bay, continuing efforts begun in the 1980s when those waters were heavily polluted,” said EPA New England Regional Administrator David W. Cash. “The proposed updated permit reflects a common-sense application of science and policy to ensure that all communities sending wastewater to Deer Island for treatment will be responsible for taking action to correct any problems within their wastewater collection systems. The draft permit also helps to address the environmental impacts facing communities with environmental justice concerns by providing cleaner water and better protected coastal resources for all to enjoy. Finally, the proposed permit addresses the climate crisis by requiring MWRA and member communities to assess the vulnerability of their assets to future severe weather threats.”

The draft permit, once finalized, will replace the previous permit in effect since 2000. The proposed updated permit makes important updates in keeping with other “National Pollutant Discharge Elimination System” (NPDES) permits issued by EPA in New England communities. New provisions in the permit include:

• Co-Permittees: The 43 communities that contribute wastewater to the treatment system will now be co-permittees along with MWRA. This approach ensures that all communities understand their obligations and are accountable under the Clean Water Act (CWA) for properly maintaining their wastewater collection systems. Other NPDES permits issued by EPA since 2000 have made contributing communities co-permittees. This is an especially important component to address the concerns of neighborhoods that have been historically overburdened with environmental contamination issues due to inadequate maintenance and capacity of their collection systems.

• Emerging Contaminants: The permit includes new monitoring and reporting requirements for per-and polyfluoroalkyl substances (PFAS) which will help EPA and other public health organizations in the broader effort of understanding these chemicals and employing effective strategies to protect public health from potentially hazardous exposure to this chemical family.

• Climate Change: The permit includes new provisions to address the threats of climate change by requiring MWRA and the member communities to assess the vulnerability of their assets to future severe weather threats.

• Combined Sewer Overflows (CSOs): The permit continues to include provisions to regulate CSOs, including a requirement that any discharges from such overflows must not contribute to the exceedance of water quality standards. The 2023 Draft Permit also incorporates CSO requirements for the four satellite collection systems (Boston Water and Sewer Commission, Cambridge, Chelsea and Somerville) that were previously in separate permits.

• Former Near-shore Outfalls Closed: The permit also stipulates that MWRA’s five nearshore effluent outfalls will no longer be authorized under the Permit as they are no longer a necessary contingency option, due to the proven reliability of MWRA’s offshore outfall in Massachusetts Bay.

To achieve better environmental and public health protection, the Draft Permit also includes updated requirements for effluent limits based on new Massachusetts Water Quality Standards and/or new data; effluent monitoring requirements for Deer Island discharges for a wide range of pollutants; ambient water quality monitoring in Massachusetts and Cape Cod Bays; implementation of an industrial pretreatment program to control the discharge of pollution into the MWRA sewer system; and updated operation and maintenance requirements, consistent with state regulations, in order to ensure that sewer system infrastructure, such as sewer pipes and pump stations, and the treatment facilities are properly operated and maintained and resilient. These include contingency measures, such as maintaining alternative power systems in case of power outages, preventing groundwater and rainwater from entering the sewer system and evaluating and implementing measures to maintain system operation in the event of major storm and flood events. These provisions are also essential components of readiness to address climate impacts on this essential infrastructure.

The permit is part of a broader effort to continue to tackle the significant issues that have plagued Boston Harbor and builds upon other recent efforts including EPA’s decision last fall to use its residual designation authority to regulate stormwater. The residual designation last fall will address non-point sources of nutrients from stormwater. This permit regulates a point source discharge of million gallons of municipal wastewater, also reducing nutrient pollution to the harbor.

More information:

EPA is accepting public comment on the updated proposed MWRA NPDES permit until July 31, 2023. EPA has also scheduled a virtual public informational meeting and a public hearing for July 12, 2023, at 7:00 pm for the information meeting and 8:00 pm for the hearing.

The full proposed permit and supporting documents, and instructions on how to submit comments and register for the public meeting and hearing, are available at: https://www.epa.gov/npdes-permits/epas-permit-massachusetts-water-resources-authority-mwra-deer-island-treatment-plant